F:
Facile = easy
Faire (en faisant) = make (making). For example, « faire 3 m. dans la m. suivante » means make 3 stitches into the next stitch, by knitting, purling and then knitting into the same stitch. Common for bobble and some lace patterns.
Fantaisie (pt fantaisie) = used to describe a somewhat uncommon stitch used in the pattern and described right at the beginning in the « points employés » (stitches used) section.
Fermeture éclair (or fermeture à glissière)= zipper
Fil = can mean either yarn or thread, depending on situation.
Fil de couleur = stitch marker. You can use a simple tied loop of a contrasting yarn, or use store-bought stitch markers.
Fleur = flower
Finitions = finishing
Fs = fois = times. As in « répéter de * à * 3 fs au tot. » (repeat from * to * 3 times total)
Former = shape, make
Fournitures = materials